* [PATCH] manual: reallocarray and str*dup interposition is not supported
@ 2021-07-20 1:43 Siddhesh Poyarekar
2021-07-20 8:05 ` Florian Weimer
0 siblings, 1 reply; 6+ messages in thread
From: Siddhesh Poyarekar @ 2021-07-20 1:43 UTC (permalink / raw)
To: libc-alpha; +Cc: carlos, fweimer
These functions call the core allocator functions (realloc and malloc
respectively) and are hence guaranteed to allocate memory using the
correct functions when multiple allocators are interposed. Having
these functions interposed in one allocator and not another may result
in confusion, hence discourage interposing them altogether.
---
manual/memory.texi | 5 +++++
1 file changed, 5 insertions(+)
diff --git a/manual/memory.texi b/manual/memory.texi
index 31ee36be8c..4560781f64 100644
--- a/manual/memory.texi
+++ b/manual/memory.texi
@@ -2033,6 +2033,11 @@ when a replacement @code{malloc} is in use. However, failure to replace
these functions typically does not result in crashes or other incorrect
application behavior, but may result in static linking failures.
+Replacing the @code{reallocarray} function and the @code{strdup} family of
+functions is not supported and may produce incorrect results. @theglibc{}
+implementations of these functions call the replacement @code{malloc} and
+@code{realloc} functions whenever available.
+
@node Obstacks
@subsection Obstacks
@cindex obstacks
--
2.31.1
^ permalink raw reply [flat|nested] 6+ messages in thread* Re: [PATCH] manual: reallocarray and str*dup interposition is not supported
2021-07-20 1:43 [PATCH] manual: reallocarray and str*dup interposition is not supported Siddhesh Poyarekar
@ 2021-07-20 8:05 ` Florian Weimer
2021-07-21 7:18 ` [PATCH v2] manual: Document unsupported cases for interposition Siddhesh Poyarekar
0 siblings, 1 reply; 6+ messages in thread
From: Florian Weimer @ 2021-07-20 8:05 UTC (permalink / raw)
To: Siddhesh Poyarekar; +Cc: libc-alpha, carlos
* Siddhesh Poyarekar:
> These functions call the core allocator functions (realloc and malloc
> respectively) and are hence guaranteed to allocate memory using the
> correct functions when multiple allocators are interposed. Having
> these functions interposed in one allocator and not another may result
> in confusion, hence discourage interposing them altogether.
> ---
> manual/memory.texi | 5 +++++
> 1 file changed, 5 insertions(+)
>
> diff --git a/manual/memory.texi b/manual/memory.texi
> index 31ee36be8c..4560781f64 100644
> --- a/manual/memory.texi
> +++ b/manual/memory.texi
> @@ -2033,6 +2033,11 @@ when a replacement @code{malloc} is in use. However, failure to replace
> these functions typically does not result in crashes or other incorrect
> application behavior, but may result in static linking failures.
>
> +Replacing the @code{reallocarray} function and the @code{strdup} family of
> +functions is not supported and may produce incorrect results. @theglibc{}
> +implementations of these functions call the replacement @code{malloc} and
> +@code{realloc} functions whenever available.
There are other examples: realpath, getcwd, asprintf, and more. So
please rephrase this in such a way that reallocarray and strdup are just
examples of memory-allocating library functions that call the
replacement malloc implementation.
Thanks,
Florian
^ permalink raw reply [flat|nested] 6+ messages in thread* [PATCH v2] manual: Document unsupported cases for interposition
2021-07-20 8:05 ` Florian Weimer
@ 2021-07-21 7:18 ` Siddhesh Poyarekar
2021-07-21 7:47 ` Andreas Schwab
0 siblings, 1 reply; 6+ messages in thread
From: Siddhesh Poyarekar @ 2021-07-21 7:18 UTC (permalink / raw)
To: libc-alpha; +Cc: fweimer
These functions call the core allocator functions (realloc and malloc
respectively) and are hence guaranteed to allocate memory using the
correct functions when multiple allocators are interposed. Having
these functions interposed in one allocator and not another may result
in confusion, hence discourage interposing them altogether.
---
manual/memory.texi | 7 +++++++
1 file changed, 7 insertions(+)
diff --git a/manual/memory.texi b/manual/memory.texi
index 31ee36be8c..5fb58af736 100644
--- a/manual/memory.texi
+++ b/manual/memory.texi
@@ -2033,6 +2033,13 @@ when a replacement @code{malloc} is in use. However, failure to replace
these functions typically does not result in crashes or other incorrect
application behavior, but may result in static linking failures.
+There are other functions (@code{reallocarray}, @code{strdup}, etc.) in
+@theglibc{} that are not listed above but return newly allocated memory to
+callers. Replacement of these functions is not supported and may produce
+incorrect results. @theglibc{} implementations of these functions call
+the replacement allocator functions whenever available, so they will work
+correctly with @code{malloc} replacement.
+
@node Obstacks
@subsection Obstacks
@cindex obstacks
--
2.31.1
^ permalink raw reply [flat|nested] 6+ messages in thread* Re: [PATCH v2] manual: Document unsupported cases for interposition
2021-07-21 7:18 ` [PATCH v2] manual: Document unsupported cases for interposition Siddhesh Poyarekar
@ 2021-07-21 7:47 ` Andreas Schwab
2021-07-21 8:04 ` [PATCH v3] " Siddhesh Poyarekar
0 siblings, 1 reply; 6+ messages in thread
From: Andreas Schwab @ 2021-07-21 7:47 UTC (permalink / raw)
To: Siddhesh Poyarekar via Libc-alpha; +Cc: Siddhesh Poyarekar, fweimer
On Jul 21 2021, Siddhesh Poyarekar via Libc-alpha wrote:
> diff --git a/manual/memory.texi b/manual/memory.texi
> index 31ee36be8c..5fb58af736 100644
> --- a/manual/memory.texi
> +++ b/manual/memory.texi
> @@ -2033,6 +2033,13 @@ when a replacement @code{malloc} is in use. However, failure to replace
> these functions typically does not result in crashes or other incorrect
> application behavior, but may result in static linking failures.
>
> +There are other functions (@code{reallocarray}, @code{strdup}, etc.) in
> +@theglibc{} that are not listed above but return newly allocated memory to
> +callers. Replacement of these functions is not supported and may produce
> +incorrect results. @theglibc{} implementations of these functions call
@Theglibc{} at the sentence beginning.
Andreas.
--
Andreas Schwab, schwab@linux-m68k.org
GPG Key fingerprint = 7578 EB47 D4E5 4D69 2510 2552 DF73 E780 A9DA AEC1
"And now for something completely different."
^ permalink raw reply [flat|nested] 6+ messages in thread* [PATCH v3] manual: Document unsupported cases for interposition
2021-07-21 7:47 ` Andreas Schwab
@ 2021-07-21 8:04 ` Siddhesh Poyarekar
2021-07-23 11:43 ` Florian Weimer
0 siblings, 1 reply; 6+ messages in thread
From: Siddhesh Poyarekar @ 2021-07-21 8:04 UTC (permalink / raw)
To: libc-alpha; +Cc: fweimer, schwab
These functions call the core allocator functions (realloc and malloc
respectively) and are hence guaranteed to allocate memory using the
correct functions when multiple allocators are interposed. Having
these functions interposed in one allocator and not another may result
in confusion, hence discourage interposing them altogether.
---
manual/memory.texi | 7 +++++++
1 file changed, 7 insertions(+)
diff --git a/manual/memory.texi b/manual/memory.texi
index 31ee36be8c..1ca0c83327 100644
--- a/manual/memory.texi
+++ b/manual/memory.texi
@@ -2033,6 +2033,13 @@ when a replacement @code{malloc} is in use. However, failure to replace
these functions typically does not result in crashes or other incorrect
application behavior, but may result in static linking failures.
+There are other functions (@code{reallocarray}, @code{strdup}, etc.) in
+@theglibc{} that are not listed above but return newly allocated memory to
+callers. Replacement of these functions is not supported and may produce
+incorrect results. @Theglibc{} implementations of these functions call
+the replacement allocator functions whenever available, so they will work
+correctly with @code{malloc} replacement.
+
@node Obstacks
@subsection Obstacks
@cindex obstacks
--
2.31.1
^ permalink raw reply [flat|nested] 6+ messages in thread* Re: [PATCH v3] manual: Document unsupported cases for interposition
2021-07-21 8:04 ` [PATCH v3] " Siddhesh Poyarekar
@ 2021-07-23 11:43 ` Florian Weimer
0 siblings, 0 replies; 6+ messages in thread
From: Florian Weimer @ 2021-07-23 11:43 UTC (permalink / raw)
To: Siddhesh Poyarekar; +Cc: libc-alpha, schwab, Carlos O'Donell
* Siddhesh Poyarekar:
> These functions call the core allocator functions (realloc and malloc
> respectively) and are hence guaranteed to allocate memory using the
> correct functions when multiple allocators are interposed. Having
> these functions interposed in one allocator and not another may result
> in confusion, hence discourage interposing them altogether.
> ---
> manual/memory.texi | 7 +++++++
> 1 file changed, 7 insertions(+)
>
> diff --git a/manual/memory.texi b/manual/memory.texi
> index 31ee36be8c..1ca0c83327 100644
> --- a/manual/memory.texi
> +++ b/manual/memory.texi
> @@ -2033,6 +2033,13 @@ when a replacement @code{malloc} is in use. However, failure to replace
> these functions typically does not result in crashes or other incorrect
> application behavior, but may result in static linking failures.
>
> +There are other functions (@code{reallocarray}, @code{strdup}, etc.) in
> +@theglibc{} that are not listed above but return newly allocated memory to
> +callers. Replacement of these functions is not supported and may produce
> +incorrect results. @Theglibc{} implementations of these functions call
> +the replacement allocator functions whenever available, so they will work
> +correctly with @code{malloc} replacement.
Looks good to me. Carlos?
Florian
^ permalink raw reply [flat|nested] 6+ messages in thread
end of thread, other threads:[~2021-07-23 11:43 UTC | newest]
Thread overview: 6+ messages (download: mbox.gz / follow: Atom feed)
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2021-07-20 1:43 [PATCH] manual: reallocarray and str*dup interposition is not supported Siddhesh Poyarekar
2021-07-20 8:05 ` Florian Weimer
2021-07-21 7:18 ` [PATCH v2] manual: Document unsupported cases for interposition Siddhesh Poyarekar
2021-07-21 7:47 ` Andreas Schwab
2021-07-21 8:04 ` [PATCH v3] " Siddhesh Poyarekar
2021-07-23 11:43 ` Florian Weimer
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